This invention relates generally to aiming devices for firearms and apparatus for mounting the same to a weapon, and more particularly to a laser aiming system having apparatus for mounting a laser to a weapon such that damage thereto from recoil developed upon the firing of the weapon is prevented.
Aiming devices are generally quite fragile. For example, telescopic sights employ a complex system of optics which can be easily damaged if subjected to great impact. Similarly, laser aiming devices are extremely fragile and would be seriously damaged by recoil if solidly affixed to the weapon. In order to prevent damage to a fragile aiming device, apparatus is required to absorb the recoil energy and reduce the shock to which the aiming device is subjected.
Recoil during the firing of a weapon occurs as a result of the weapon being accelerated rearwardly relative to its position prior to firing. Anything solidly affixed to the weapon will be subjected to the recoil of the weapon. Attempts to solve the problem of recoil damage to aiming devices, typically a telescopic sight, have followed the principle of permitting the aiming device to move relative to the weapon with some type of energy dissipating mechanism absorbing the energy created upon firing. Thus, upon being fired, the weapon would move rearwardly relative to the aiming device, preventing full impact of recoil from being applied to the aiming device.
One of the earliest mounting mechanisms using the relative sliding approach is the telescope sight for firearms patented by F. F. Burton in 1907 as U.S. Pat. No. 870,272. The apparatus disclosed by Burton comprises a telescopic sight that is free to slide with respect to its mounts on the weapon with recoil energy being dissipated through the friction developed between the mounts and the sight body.
A slightly more sophisticated system also employing a sliding mount for the aiming device is that disclosed in U.S. Pat. No. 1,641,019 issued to J. D. Woods. Woods discloses a gun sight which is slidably mounted in ring supports attached to the barrel of the weapon with a coil spring operably disposed between the sight and the forward support ring. In Woods, the coil spring permits rearward movement of the weapon with respect to the sight and returns the sight to its initial position after the recoil is dissipated. A similar approach implemented by different apparatus is the telescope mount of E. L. Livermore, which is the subject matter of U.S. Pat. No. 2,510,289. In the arrangement of Livermore, a quick disconnect telescope mount having shock absorbing capabilities is provided wherein the telescope sight is mounted for sliding movement with shock absorption resulting from the transmission of recoil forces from the weapon via a ring to a pin which is loaded by a spring. This mounting permits limited rearward movement of the weapon with respect to the sight with the spring returning the sight to its initial position after recoil.
Subsequent attempts to develop a mount for delicate aiming devices have retained the feature of providing the aiming device with movement relative to the weapon; however, the single shock absorbing mechanism has been replaced by fore and aft shock absorbing mechanisms. An example of this approach is the telescope sight mount of T. R. Felix disclosed in U.S. Pat. No. 2,597,466. In the apparatus disclosed, a clamp is rigidly secured to a slidable telescopic sight having a lug extending from the clamp that fits into a socket joint so as to move longitudinally with the sight. A pair of rubber blocks are positioned in the socket on opposite sides of the lug and function as shock absorbers to insulate the sight from the recoil force.
Illustrative of mounting apparatus using dual coil springs is the telscope sight mount of U.S. Pat. No. 3,153,856, also issued to T. R. Felix. The apparatus slidably mounts the aiming device with a lug being secured to the telescopic sight and logitudinally movable in a slot in the mount. A guide rod is disposed in the slot and firmly mounted at its ends to the mount body, with the mounting lug slidable thereon. A pair of compression springs are disposed about the rod on opposite ends thereof in engagement with the corresponding end of the slot and the face of the mounting lug opposing that end of the slot. By virtue of this arrangement, when the rifle is fired, or when some other shock is imposed on the stock, the telescopic sight can move longitudinally against the action of the springs, with the springs returning the sight to its initial position after recoil.
Although the prior art involves the mounting of optical aiming devices such as telescopic sights to firearms, it is also desirable to mount other types of aiming devices in a manner such that they are cushioned from the shock of recoil. In fact, the problem of damage due to recoil force becomes much more acute when other types of aiming devices, such as lasers, are used which are even more delicate than the optical telescopic sights. Typically, laser aiming devices will have miniature electronic components and other delicate internal components that may easily be damaged by the recoil of a conventional firearm, if the laser is rigidly mounted or otherwise not insulated from recoil.
A popular laser for use as an aiming device in conjunction with a conventional firearm such as a pistol or rifle is the helium neon laser. The popularity of the helium neon laser tube results from its relative inexpensiveness and also from the relative simplicity of its required power supply as compared to other types of laser tubes. However, the helium neon laser tube is one of the more delicate types of lasers primarily due to a glass capillary tube internal to the helium neon laser tube. If the laser tube is not cushioned from the shock of recoil, a resonant frequency may be set up in the glass capillary tube during firing of the weapon, causing the tube to break.
Another problem somewhat unique to laser aiming devices involves their ability to remain operative during automatic or rapid firing of the weapons to which they are attached. If the laser tube is not sufficiently insulated from the recoil forces of automatic firing, misalignment of mirrors internal to the laser can occur which causes the laser tube to flicker or possibly extinguish. If the tubes begin to flicker to extinguish, it is possible that the operator of the weapon will lose sight of his target.
Accordingly, it is desirable when using a laser as an aiming device to have an apparatus suitable for mounting the laser aiming device, particularly a helium neon laser tube, to a conventional firearm, such that the laser tube is insulated from the recoil of the weapon, thereby preventing damage to the laser tube and permitting continuous operation.